Long COVID and Sleep: Insomnia, Hypersomnia, and Circadian Disruption

Sleep disturbance is one of the most prevalent and disabling symptoms in Long COVID, reported by 50–80% of patients in various studies. Yet it is also one of the most heterogeneous — some patients cannot sleep at all, others sleep 12–16 hours and still feel exhausted, and many experience a complete disruption of their normal sleep-wake cycle. Understanding which type of sleep problem you have is essential for finding effective treatment.

Types of Sleep Problems in Long COVID

Insomnia

Difficulty falling asleep, staying asleep, or waking too early is reported by approximately 40–50% of Long COVID patients. Long COVID insomnia appears to have multiple contributing factors:

• Autonomic nervous system dysregulation: Hyperactivation of the sympathetic nervous system (the "fight or flight" system) makes it difficult to transition into the parasympathetic state needed for sleep. This is particularly common in patients with POTS or hyperadrenergic dysautonomia.
• Neuroinflammation: Inflammatory cytokines disrupt the normal sleep architecture, reducing slow-wave sleep and REM sleep.
• Pain and discomfort: Widespread pain, palpitations, and other physical symptoms interrupt sleep.
• Anxiety and hypervigilance: The psychological burden of chronic illness, combined with possible neurological changes, can create a state of hyperarousal that prevents sleep onset.

Unrefreshing Sleep

Many Long COVID patients sleep a normal number of hours but wake feeling completely unrestored — as if they had not slept at all. This is the hallmark sleep symptom of ME/CFS and is also common in Long COVID, particularly in patients who meet ME/CFS criteria.

Polysomnography (sleep studies) in ME/CFS and Long COVID patients often shows reduced slow-wave (deep) sleep and abnormal alpha wave intrusion into non-REM sleep — a pattern associated with unrefreshing sleep and pain.

Hypersomnia

Some Long COVID patients experience the opposite of insomnia — they sleep excessively, sometimes 12–18 hours per day, and still feel exhausted. This is distinct from the fatigue of ME/CFS (which involves exhaustion without necessarily sleeping more) and may reflect a different underlying mechanism, possibly involving hypothalamic or brainstem involvement.

Circadian Rhythm Disruption

A significant proportion of Long COVID patients report that their sleep-wake cycle has shifted dramatically — becoming severely delayed (unable to sleep until 3–5am, unable to wake until noon or later) or completely irregular. This circadian disruption may reflect direct viral effects on the suprachiasmatic nucleus (the brain's master clock) or on melatonin production.

The POTS-Sleep Connection

For Long COVID patients with POTS, sleep problems have an additional autonomic dimension. POTS is associated with:

• Nocturnal tachycardia that disrupts sleep
• Supine hypertension (blood pressure rising when lying down) that causes discomfort
• Adrenaline surges at night that cause awakening with a racing heart
• Nocturia (frequent nighttime urination) due to fluid redistribution when lying down

Treating the underlying POTS often improves sleep quality significantly. Beta-blockers taken at bedtime can reduce nocturnal tachycardia. Elevating the head of the bed 10–30 degrees can reduce supine hypertension and improve overnight fluid balance.

Treatment Approaches

Sleep Hygiene (Modified for Long COVID)

Standard sleep hygiene advice (consistent sleep schedule, dark room, no screens before bed) is a reasonable starting point but often insufficient for Long COVID patients. Key modifications:

• Avoid pushing through fatigue to maintain a schedule — in patients with PEM, forcing activity to maintain a sleep schedule can trigger crashes. Flexibility is important.
• Manage the sleep environment for autonomic symptoms — cool room temperature, elevation of the head of the bed, and compression garments removed before sleep.
• Avoid vigorous exercise close to bedtime — for POTS patients, evening exercise can cause adrenaline surges that disrupt sleep.

Melatonin

Low-dose melatonin (0.5–1mg, taken 1–2 hours before desired sleep time) can help reset the circadian clock in patients with delayed sleep phase. Higher doses (3–10mg) are commonly used but may be less effective for circadian shifting and can cause grogginess the next day.

Low-Dose Tricyclics and SNRIs

Low-dose amitriptyline (10–25mg at bedtime) or low-dose trazodone (25–50mg) are commonly used for unrefreshing sleep in ME/CFS and Long COVID. They increase slow-wave sleep, reduce pain, and have mild sedating effects. They are not habit-forming at these doses.

Low-Dose Naltrexone (LDN)

LDN taken at bedtime has been reported by many Long COVID and ME/CFS patients to improve sleep quality, reduce pain, and improve energy the following day. The proposed mechanism involves reduction of microglial activation and neuroinflammation during sleep. Clinical trial evidence is emerging.

Addressing Autonomic Dysregulation

For patients whose sleep problems are primarily driven by autonomic dysregulation (nocturnal tachycardia, adrenaline surges, POTS), treating the underlying autonomic dysfunction is the most effective approach. This may include beta-blockers, ivabradine, or clonidine at bedtime.

When to Seek a Sleep Study

A formal polysomnography (sleep study) is warranted if:

• You have symptoms of sleep apnea (snoring, witnessed apneas, morning headaches)
• Your sleep problems are severe and not responding to initial treatment
• You have significant daytime hypersomnolence that is impairing function

Sleep apnea is more common in Long COVID patients than in the general population, possibly due to upper airway inflammation or autonomic effects on respiratory drive.